The invention relates to a thin film alloy material with the design of optic reflection and semi-transmission. In particular, the invention relates to a single layer thin film alloy material, which has tie effect of reflection and semi-transmission simultaneously, and can attain different reflectivity and half-transmittance by adjusting the ratio of alloy as well as the thickness of thin film.
Along with the great stride of electric technology, photoelectric industry, such as CD industry and flat panel display industry etc. developed a great deal of consumption products, in which metal reflective film plays the necessary role. The characters of metal reflective film such as reflection, half-reflection, beam-split, light filtering etc. can be used to design different optic devices.
In the reflection process of CD, a laser beam with high resolution transmits the polycarbonate substrate, reaching to the reflective layer, on which the beam focuses on the information pits so as to read the disc. The laser beam moves along with the tracks on CD, focusing on the alternately pits and planes to generate destructive interference as well as constructive interference, and then forms the digital signal xe2x80x9c1xe2x80x9d or xe2x80x9c0xe2x80x9d, which can be shown as music or computer program after electric decoding.
Generally, the higher conductive coefficient of metal is, the higher reflectivity will be. So most metal reflective materials are the high conductivity materials such as Au, Ag, Al, and Cu etc. In general, the reflection layer of the disc is placed on the plane that has pits and can transmit information. The mast common materials of it are aluminum or aluminum alloy (such aluminum-zirconium alloy); moreover, in flat panel displays (such as TFT-LCD, PDP, OLED), aluminum alloy (such as aluminum-neodymium alloy) is also a necessary material of conductive film.
Recently, the era of DVD that has high capacity, high audio quality, and high-definition is coming. Many thin films of different functions in DVD disk are formed with certain target materials by such as sputtering method. Wherein there are two information film layers in the double-side-single-layer DVD disk played with one side. The first layer is a high reflection layer, i.e. a common total reflection layer, and the second layer is a half-reflection layer, of which the reflectivity is among 18xcx9c30%. Besides reflecting light, the second layer also needs to be transmitted by substantial light beam so that the laser can access to the high reflection layer and return to the signal detector though the half-reflection layer.
The common materials of half-reflection layer are pure gold is and silicon. Gold can reflect light and can be transmitted by light; moreover, it has better character of anti-corrosion and is easier to form a uniform film by sputtering, but it is very expansive. Silicon also has drawbacks such as that its deposition rate and deposition amount is less than gold and that it easily reacts with oxygen and nitrogen. So in the past few years, the whole world has enthusiastically researched the ingredient and the fabrication process of new materials. FIG. 1 is a schematic diagram of the multi-layer thin film material with the design of reflection and half-reflection of the prior art, which mainly comprises: a transparent substrate 120, a half-reflection layer 130 that has the first pit pattern 115, a transparent interval layer 125, and a high reflection layer 135 that has the second pit pattern 105. When the light beam from laser 140 indicates to substrate 120, reflected by half-reflection layer 130 and high reflection layer 135, it will be eventually detected by the photodetector 145 that can sense the modulation of light intensity based on whether there is a pit on a certain point of the reflection layer.
However; in such structure of prior art, both the half-reflection film and high reflection film must be coated on the substrate as a multi-layer thin film structure. For the CD manufacturers, the complicated structure and fabrication process are so burdensome that the cost cannot be reduced, delaying the technology.
The major objective of the present invention is to provide a thin film alloy material with the design of optic reflection and semi-transmission, which can attain the effect of reflection and semi-transmission simultaneously.
Another objective of the present invention is to provide a thin film alloy material with the design of optic reflection and semi-transmission, which can be coated on the both sides of a single layer film to from total reflection layer and semi-transmission simultaneously.
The other objective of the present invention is to provide a thin film alloy material with the design of optic reflection and semi-transmission, which not only can make a single layer film have the effect of reflection and semi-transmission simultaneously, but also can attain the effect that has different reflectivity and half-transmittance by adjusting the ratio of alloy and the thickness of thin film.
To attain the foregoing object, the present invention provides a thin film alloy material with the design of optic reflection as well as semi-transmission, and a thin film that has top and bottom two sides, on which there are the first alloy layer and the second alloy layer coated. Wherein:
The first metal alloy layer is composed of silver (Ag) and metal X, and wherein the metal X is chosen from one of the following metals: titanium (Ti), zirconium (Zr), hafnium (Hf);
The second metal alloy layer is composed of silver (Ag), copper (Cu), and metal X, and wherein the metal X is chosen from one of the following metals: titanium (Ti), zirconium (Zr), hafnium (Hf);
It is preferable that the content of metal X accounts for 0.01%xcx9c10% of the first metal alloy layer, and the content of metal X accounts for 0.01%xcx9c10% of the second metal alloy layer.
For your esteemed reviewing committee members to further recognize and understand the invention in more complete way, a detailed description of the invention in matching with corresponding drawings are presented as following and hope they will benefit your esteemed reviewing committee members in reviewing this patent application favorably.